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Is Bayer killing our bees? Imidacloprid as potential cause of CCD

I found the following on the BBKA site:

>>French and Swiss researchers found that after Imidacloprid is dusted onto sunflower seed, or oilseed rape, it permeates the entire plant, including the nectar, pollen and seeds. The loss of bee colonies in France was concentrated in sunflower or oilseed rape growing areas. Imidacloprid only needs to be present at 10 parts per billion to kill bees outright. Bees exposed to 5 ppb simply do not return to their hives.

A definitive Swiss study reported:

ABSTRACT:

“Klaus Wallner confirmed in his study of Imidacloprid prepared Phacelia with a burden of 50 g/hectare, that the bee’s honey-sac average contamination was 5ppb and the pollen taken from the 'pollen baskets' of the bees contained 7ppb. The centrifuged honey contamination level could not (yet) be ascertained. The level was less than the 3ppb trace ability level for honey.

Clarification in France:
In a report issued by the French Agriculture Ministry it was stated: According to the sunflower variety the residues in the flower on the 65th day (at start of blossom period) varied between 2.5ppb (Pharon) and 8.7ppb (Natil). These values could possibly be higher at point of harvest. The sunflower pollen is contaminated at an average level of 3ppb (up to 11 ppb max.). In untreated plantings (sunflower, rape and corn), which were planted in Imidacloprid-contaminated-soil, up to 7.4ppb was detected in the flowers.

“The Bayer study produced a mortality rate due to Imidacloprid for bees as follows: The LD 50 (the lethal dose which kills 50% of test organisms within 48 hours) lay between 3.7 and 40.9 Nanogrammes of Imidacloprid per bee. Long term injury was investigated by Bonmatin. He achieved an LD 50 after 8 days by feeding individual bees an Imidacloprid/ sugar solution of 0.1 ppb. The substance showed itself to be highly toxic when delivered over time.”

But the symptoms of Imidacloprid poisoning are nothing like
what is seen with CCD.

Sounds like Jerry Hayes seems to think theres at least the possibility of a linkage:

HAYES: Um you know the ultimate answer on that is still out. But yes you're right Steve there is a class of insecticides called neonicotinoids, of which, ah, an active ingredient called imidacloprid has been banned in some countries in Europe because of its association with damaging, ah, pollinators. It has a tendency to, at least in the European data, to have the bees forget how to get home. And so this is one of the components that we're seeing here. And these neonicotinoids and imidacloprid is used pervasively in agriculture in the U.S. Primarily it's a systemic. So it does what it's supposed to do on harmful agricultural pests but it's working its way through the plant up into the flowers and getting into the nectar. Ah, in doses that will not kill a honeybee out right. So the question is what are the chronic long-term 24/7 365 exposures doing to the honeybees and is this a component of the problem?

Imidacloprid has been around since the late 1980s, and was already as heavily used in the mid 1990s as it is now. Why wouldn't "CCD," if imidacloprid is the cause, have shown up long before this?

That's one of the questions for sure. I also wonder how imidacloprid could account for the wide geographical distribution of the reported losses. I could understand an impact in a localized region with a predominance of one kind of forage, bloom times, etc. It sure seems too widespread for a single insecticide.

>>>Why wouldn't "CCD," if imidacloprid is the cause, have shown up long before this?<<<
Increased saturation levels? Some substance have a cumulative effect which takes a while to show up in the environment. There are lots of examples. Heavy metals are an obvious one. Dioxins are all throughout our environment now. At a certain saturation point they are a big problem.
DDT didn't outright kill birds but the effect was similar if it effected their reproductive cycles.
Theoretically, the cumulative effect of continued and increasing use of neonicotinoids could cause increasing problems as well.

>>>But the symptoms of Imidacloprid poisoning are nothing like
what is seen with CCD.<<<
The fact that nonlethal doses interfere with the bees memories seems to be consistant with part of what we are seeing in CCD,ie bees that leave the colony and don't return. Not sure how the non-robbing would figure in though.

<<<It sure seems too widespread for a single insecticide.<<<
Read up on the uses of these pesticides. It isn't just one pesticide and it is also used just about everywhere, from what I can tell, from golf courses to suburban lawns to various agricultural uses.

About half the posters re neonicotinoids are saying this is an old syndrome so they can't be responsible. The other half is saying it is a new different syndrome so this class of substances can't be responsible.

I'm not convinced it IS this class of substances but why are so many willing to consider beekeeper applied chemicals and poo poo to possibility of imidacloprid and the like?
Sheri

About half the posters re neonicotinoids are saying this is an old syndrome so they can't be responsible. The other half is saying it is a new different syndrome so this class of substances can't be responsible.

I'm not convinced it IS this class of substances but why are so many willing to consider beekeeper applied chemicals and poo poo to possibility of imidacloprid and the like?
Sheri

I'm just asking questions. At this point everything's on the table. As far as I can tell, no one who is conducting the research has released much data, so I guess we'll just have to wait until the experts tell us what their conclusions are.

Coyote, my reply wasn't meant to be critical of your post. Questioning is a good thing, I was just adding my understanding as to the prevelance of these pesticides.
I totally agree with you, everything SHOULD be on the table, that was my point as well.
Sheri

Imidacloprid has been around since the late 1980s, and was already as heavily used in the mid 1990s as it is now. Why wouldn't "CCD," if imidacloprid is the cause, have shown up long before this?

Change in imidacloprid formulation/application uses could be an answer. Also it may not be correct to attribute CCD or any other syndrome to a single cause. Parsing out cause and effect relationships frequently shows that permissive factors play a strong role. For instance, DWV usually does not cause apiary problems without varroa, but has been successgully treated with bacteriostatic antibiotics. Does this mean that bacteria cause DWV? How about varroa? Does Apistan kill DWV? What if your queen is infected and showing transovarial transmission. Epidemiology and pathology are complicated and their finding must be interpreted with care. If you don't ask essential questions, you only find misleading answers.

Change in imidacloprid formulation/application uses could be an answer. -Aspera

I agree that it COULD be. I doubt imidacloprid, or any changes in formulation or application, is solely responsible for CCD, though.

Why not pick out a different chemical? Imidacloprid is widely used, but so are any number of other insecticides. Why not point fingers at them? What makes imidacloprid different under these circumstances?

And -- although this is along a different line -- why are bees apparently suddenly able to detect toxicity of imidacloprid or some other insecticide(s) (they don't rob out hives killed by CCD, right?), even though they apparently could not detect that toxicity when they collected the pollen (or possibly nectar)?

>>>What makes imidacloprid different under these circumstances?<<<
I think the reason there is focus on imidacloprid is the lawsuit and settlement by Bayer over this very issue in Europe.

>>>why are bees apparently suddenly able to detect toxicity of imidacloprid or some other insecticide(s) (they don't rob out hives killed by CCD, right?), even though they apparently could not detect that toxicity when they collected the pollen (or possibly nectar)?<<<
Good question.
Sheri

fromWikipedia via the BBKA board

Imidacloprid (IUPAC name (EZ)-1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine) is an insecticide manufactured by Bayer Cropscience (part of the drug and chemical conglomerate Bayer AG). It is sold under the trade names Merit, Admire, Gaucho, Confidor, Premise and Winner, as well as Hachikusan (in Japan) and Premise for termite control, and Advantage in the US and Europe for flea control on pets.

Imidacloprid was first patented in the United States in U.S. Pat. No. 4,742,060, on May 3, 1988, by Nihon Tokushu Noyaku Seizo K.K. of Tokyo, Japan.

In France, its use (as Gaucho) has become controversial in terms of a possible link to derangement of behavior in domesticated honeybees. See Imidacloprid effects on bee population.

[edit] Biochemistry
A chlorinated analog of nicotine, the compound therefore belongs to the class of chloronicotinyl insecticides, and acts on the nicotinic acetylcholine receptor; the chlorination inhibits degradation by acetylcholine-esterase. Imidacloprid is notable for its relatively low toxicity to most animals other than insects due to its specificity for this type of receptor, which is found more often in insect nervous systems and zooplankton than that of other animals (exceptions exist; earthworms and a few species of fish, for example). This improved ratio of toxicity allows the use of very low concentrations (e.g. 0.05-0.125 lbs/acre), making it safer for insect control than other neurotoxins (particularly organophosphates) and enabling its use in applications as diverse as flea treatments for pets, control of beetle larvae in lawns, eradication or prevention of termite infestation in buildings, and other uses where animals and people may be exposed. Imidacloprid is, for example, present as a main (or the sole) active ingredient in concentrations between five and ten percent in three out of the four most widely used flea treatment and preventative topical treatments for dogs in the United States; these manufacturers claim an effective killing persistence of at least four weeks. The compound is also used for flea treatment on cats, whose livers have only limited detoxification ability compared to dogs and humans.

Imidacloprid is rated as "moderately toxic" acutely by the WHO and the EPA (class II or III, requiring a "Warning" or "Caution" label), and a "potential" ground water contaminant. It is rated as an "unlikely" carcinogen by the EPA (group E), and is not listed for endocrine, reproductive, or developmental toxicity, or as a chemical of special concern by any agencies. It is not banned, restricted, cancelled, or illegal to import in any countries. Tolerances for imidacloprid residue in food range from 0.02 ppm in eggs to 3.0 ppm in hops.

Animal toxicity is similar to that of the parent compound, nicotine; fatigue, twitching, cramps, and weakness leading to asphyxia. The oral LD50 (the dose which resulted in mortality of half of the test animals) of imidacloprid is 450 mg/kg body weight in rats and 131 mg/kg in mice; the 24-hour dermal LD50 in rats is greater than 5,000 mg/kg. It is not irritating to eyes or skin in rabbits and guinea pigs (although some commercial preparations contain clay as an inert ingredient, which may be an irritant). The acute inhalation LD50 in rats was not reached at the greatest attainable concentrations, 69 mg/cubic meter of air as an aerosol, and 5,323 mg/cubic meter of air as a dust. In rats subjected to a two year feeding study, no observable effect was seen at 100 ppm. At 300 ppm females showed decreased body weight gain and males showed increased thyroid lesions, while females showed increased thyroid lesions at 900 ppm. In a one year feeding study in dogs, no observable effect was seen at 1,250 ppm, while levels up to 2,500 ppm led to hypercholesterolemia and elevated liver cytochrome p-450 measurements. Reproductive studies in rats resulted in no observable effect at 100 ppm and decreased pup weight at 250 ppm; developmental toxicity studies in rats showed no observable effect at 30 mg/kg/day and skeletal anomalies at 100 mg/kg/day, while in rabbits no observable effect was detected at 24 mg/kg/day and skeletal abnormalities at 72 mg/kg/day. Imidacloprid was negative for mutagenicity in 21 out of 23 different laboratory tests, but was positive for chromosomal changes in human lymphocytes and for genotoxicity in CHO cells. No carcinogenicity was seen in rats fed up to 1,800 ppm of imidacloprid for two years.

Imidacloprid has low vapor pressure. The chemical breaks down to inorganic molecules by both photolysis and microbial action, in the air and with a half-life of 30 days in water and 27 days in soil anaerobically. Although it is not "persistent" in the technical sense since it does degrade, it can, however, have a half-life in soil under aerobic conditions of as long as 997 days, which is the cause of the concern over possible water contamination as it gradually leaches out of a hypothetical soil reservoir. The manufacturer maintains that, when applied according to instructions, such long-term contamination is only found as the result of "repetitive application over several years" and spread to beneficial insect populations is minimal. In the body, 96% of the chemical is eliminated within 48 hours; the most important degradation product in the body is 6-chloronicotinic acid, another nicotinic neurotoxin with similar properties. Imidacloprid has, however, been reported to degrade into toxic, persistent, 2-chloropyridine.

[edit] Proper Use of Advantage
When using Advantage flea medicine on animals, make sure to use a soap-free shampoo. Bayer's website states it is safe to shampoo[1], however, the company's question hotline informs otherwise, stating that it is necessary to use a soap-free shampoo with an oatmeal base, otherwise the product will be removed.

[edit] A systemic insecticide
Imidacloprid is taken up by plant roots and diffuses in the plant vascular system, where insects ingest it by sucking the plant fluids. The products Confidor and Admire are meant for application via irrigation, application to the soil, or on foliage, while Gaucho is intended for use as a seed dressing, applied to the seed before sowing.

Seed applied insecticides are often used to deal with numerous insects as they are easy to use and comparable in cost to most traditional insecticides used at sowing time. Some also indicate that it might be better for the environment because less chemical is required than for broadcast or banded applications, or at least because less chemical is sprayed in the air. However, some note that the use of seed-applied insecticides at each season implies the chemical is used whether there is need to fight insects or not.

And -- although this is along a different line -- why are bees apparently suddenly able to detect toxicity of imidacloprid or some other insecticide(s) (they don't rob out hives killed by CCD, right?), even though they apparently could not detect that toxicity when they collected the pollen (or possibly nectar)?

I'm new here so don't take this out of line but maybe the robbers can't find their way back? Has anyone tried using the frames out of a CCD hive in a "normal" hive with no results?

While researching this subject for Apr ABJ, I talked a number of researchers. A plant geneticist wondered if Nicotinoids were so prevalent that they were in the water used to mix HFCS. He was talking about the GROUND WATER. He wondered if the drought could have distilled the mix concentrating it as irrigation water was recycled. He was not a hydrologist. He sent me the link below. It's a letter from 2003. It frightens me.

Jim, you're involved with Long Island. Did you know about this? Make the link work somehow and read it and weep.

There's a lot of potatoes grown on Long Island, and I have heard
of soil applications that may have been the root cause of this problem
("in-furrow applications of Admire in potatoes and vegetables...").

We have a meeting next Sunday (Larry Connor will be speaking)
so I will ask if there has been any problems noticed as a result
of this groundwater contamination.

Read it and weep...

It figures...

Just another piece to an immense and deadly puzzle. I'm disgusted by the corporate agri-conglomerates and their complete and utter disregard for the rest of humanity's well being.

You may have heard that the FDA is approving one of the best and strongest antibiotics we have available for human bacterial infections, for the treatment of bovine pneumonia. These antibiotics are a last line lifesaver for bacterium that cannot be beat by other treatments. Now you're going to find them in trace ammounts in every bite of beef you ingest. Have you ever known any farmer/rancher to ever use products as labeled? Even Beeks use Tetracyclin as a prophylactic to control AFB. What do suppose happens? Think anything else builds resistances?

So when some influenza attacks the human race, and the weak start to succumb to opportunistic bacterial infections, thank the cattle ranchers and milk producers for depriving us of a last ditch antibiotic.

All to make a few more bucks.

Next time you buy groceries, think about going to the local farmer's market and supporting local farmers working in a sustainable manner.

Albert

September 8th 2007 is National Beekeeping Day
American Agriculture, its as close as the nearest Honeybee!

I think it's only used as a soil application. It goes in with the seeds. In France they found it in nearby plants that were untreated.

In any case this was the first thing the CCD team looked at. Bees died where there no treated crops anywhere near. Re: pesticide in the hive...there was at least one organic guy who lost a lot of bees. There were varieties of treatments.